Redcode file integrity etc

[Seth Larney]

Hey all,

This may be a question for Graham. I'm pitching to couple of features down here in Australia to bring me on as Post Supervisor (I've post supervised 14 shorts, and I was Technical Supervisor on Superman Returns), and I'm just trying to clarify a few of the finer points of what we can expect with Redcine.

This may be an academic question, as the Red team may very well have not come accross this in practice yet, but I'm wondering how Redcode handles damaged sectors and info within a single Redcode file. I.e, if a particular Redcode take gets damaged somehow (maybe the header, or any other part of the file), how easy is it to read the rest of the shot out.

I'm pretty sure this hasn't been asked before, buy my apologies if it has. Also, if it's a question that's way to early to answer, then totally understood.

Cheers,
Seth.

 

[Gavin Greenwalt]

I asked a similar question in relation to what would happen if the camera were to for some reason unmount HDD/crash/powerdown/overload in the middle of the take.

The official RED response was that recovery tools would ship with the camera to restore corrupted reference files.

The exact response was in relation to an unexpected End of File situation however I assume it could handle similar situations where the bad sector is not at the end.

 

[Seth Larney]

Thanks very much Gavin, thats a good sign.

 

[Alexander Black]

One would hope it would just drop the frame(s) affected, or let you get fancy and restore missing parts of the image from neighboring frames.

For bad data post-copy (i.e. after you have ingested it) will be nice to have ZFS and avoid crap like that forevermore..

_a

 

[Seth Larney]

Too true,

It would be nice to get some sort of insight into what the guys think about this. Graham, if you're listening, I know this might be something that you guys haven't come accross, but do you have any thoughts on how we'll fare with bad sectors inside of a Redcode file ? I.e if you had that 10 minute steadycam money shot from Children of Men.. then had to recover the file from a slightly damaged hdd..

Cheers,
Seth.

 

[Rob Lohman]

This is actually a Rob question The compression works on single frames, so recovery outside of corrupt frames should be good. We are looking into tools to extract good frames from a corrupt movie and so on.

The worst case would be file system corruption where you might not be able to see a file or miss sections etc. In such cases you might want to run a disk / file recovery tool first before putting it through our stuff.

While we've sometimes talked about such tools we have not stated if or when you would get such tools. Just to be clear on that. But it is something I've looked at extensively.

 

[Seth Larney]

Hey Rob, I should have known this was one for you Thanks very much for taking the time to reply !

That's pretty great news. Recovery of files from corrupt file systems etc are one thing (and something that is applicable to any data centric workflow), but it's great to know that you are thinking about the recovery of data from the files (as you obviously would be). If we get to a stage where when we've recovered corrupt files, we can then extract useable data fairly successfuly, then our bases will be pretty well covered.

Thanks again,
Seth.